Lemongrass Oil Containing Chitosan Microcapsules by Ionotropic Gelation

Ionotropic gelation using sodium tripolyphosphate (STPP) as the crosslinker was successfully used to formulate lemongrass oil containing chitosan microcapsules. Formation of oil in aqueous chitosan polymer solution was followed by crosslinking with STPP. Optimum formulation for the synthesis of microcapsules was found varying the amounts of lemongrass oil (1-3 g), chitosan solution (1-2%) and STPP (0.5-1.0 g). Microcapsules were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and stage microscope. Encapsulation efficiency, oil content, oil load and release rates were determined by UV-visible spectroscopy. The SEM images indicated that the oil loaded capsules are spherical in shape and possess a smooth surface and their size varied between 100-1000 nm. FTIR spectra confirmed successful encapsulation of lemongrass oil within chitosan. At polymer: 1 g, oil: 3 g and crosslinker: 0.5 g gave microcapsules with higher stability and steady controlled release.